The following services will be provided to investigators through the Tissue Culture Core: Instruction of staff in the appropriate techniques for tissue culture and for the use of the Tissue Culture Core. This is critical for a multiuser laboratory to ensure minimal risk of contamination, which could affect stock cell cultures or cells in use by other investigators. . Maintenance of sterile stock media (MEM, DMEM, Hams F12, Sf900, Williams E). 3. Maintenance of tested lots of fetal bovine serum and calf serum and of other supplements needed for preparation of working tissue culture medium (antibiotics, L-glutamine, HEPES, vitamins, bicarbonate, etc.). . Maintenance of stocks of sterile glassware, plasticware, centrifuge tubes, pipets, etc. 5. Maintenance of LN2 freezer for storage of cells. 6. Scheduling usage, maintenance and yearly certification of laminar-flow biohazard hoods. 7. Daily inspection and monitoring of all CO2 incubators with biweekly cleaning and maintenance. 8. Mycoplasma testing of all cells. For this the Gen-probe kit supplied by Gen-Probe,tnc., San Diego, CA will be used. No cell lines can be used for culture in the core unless they have been tested free of mycoplasma. All other cell lines are tested periodically to assure that they are mycoplasma-free. . In addition to the services indicated above, the tissue culture core will maintain frozen stocks of commonly used cell lines (COS1, HepG2, CaCo2, CHO, Sf9 McA-RH7777, and special cells including human fibroblast lines) and will, upon request, assist investigators in scaling up the number of stock cells necessary for experiments. The investigators will be required, however, to provide their own technical help to carry out the actual experimental protocols. E. Facilities The tissue culture for the Program Project Building, the same floor laboratory equipped with: PHS 398/2590 (Rev. 05/01) facility that is currently being used by the investigators and will be available is centrally located in Room 6021 on the sixth floor of the Hanes Research as the laboratories of the Program investigators. It is a 400 sq. ft. wet Page "_i